Polymerization process for drag reducing substances

ABSTRACT

A method is provided for the production of ultrahigh molecular weight drag reducing substances and the like comprising: 
     (a) preparing under an inert atmosphere a catalyst comprising: p1 (1) titanium halide of the general formula TiX m  wherein m=2.5 to 4.0; 
     (2) a co-catalyst of the formula AlR n  X 3-n  where R is a hydrocarbon radical, X is a halogen or hydrogen and n is 2 or 3; 
     (3) a phosphorous compound of the formula PR 1  R 2  R 3  or P(OR 1 ) (OR 2 ) (OR 3 ) where R 1 , R 2 , and R 3  are, independently, aryl, alkyl, aralkyl, or alkaryl, containing from 1 to 12 carbon atoms and placing the catalyst in contact with; 
     (b) alpha-monoolefinic hydrocarbons from C 2  -C 30  under suitable temperature conditions to provide a hydrocarbon soluble ultrahigh molecular weight polymer, then ceasing polymerization at a polymer content level of 20% by weight or less, based on the total reaction mixture.

This reference is a continuation-in-part of Ser. No. 7,088 filed Jan.29, 1979, now abandoned, which in turn was a continuation-in-part ofSer. No. 953,144, filed Oct. 20, 1978, now abandoned.

This invention relates to a method for the production of ultrahighmolecular weight polymers suitable for use as drag reducing agents. Moreparticular, this invention provides a method for the production ofultrahigh molecular weight polymers using a modified Ziegler-Nattasystem while ceasing polymerization at low levels of polymer contentbased on the total reaction mixture.

It is well known that alpha-olefins may be polymerized in the presenceof a catalyst generally referred to as a Ziegler-Natta catalyst. Thesecatalysts generally consist of materials such as a titanium trihalideand organometallic cocatalysts such as aluminum alkyls or alkyl halides.

This basic catalyst system has been modified in many ways including athree component olefin polymerization catalyst containing alkyl aluminumsesquihalide and transition metal compounds such as disclosed in U.S.Pat. No. 2,951,066. The catalyst comprises a mixture of an alkylaluminum sesquihalide, a transition metal halide, and a phosphinecompound. The invention was designed to provide a method for thepolymerization of alpha-monoolefins to yield high molecular weightcrystalline polymers such as high-density polyethylene. These polymersare taught to be insoluble in solvents at ordinary temperatures, behighly crystalline and be suitable for molded objects exhibiting a highdegree of stiffness. The process provides for a temperature range offrom 0° C. to 250° C. and reaction pressures from atmospheric to about20,000 pounds per square inch (psig).

U.S. Pat. No. 3,004,015 relates to an improved polymerization methodusing a stibine compound of the formula SbR₃ used as a modifier in thepolymerization of alpha-olefins; stibine replaces phosphorus in theprocess. Both these materials contain Group VA elements.

U.S. Pat. No. 3,081,287 utilizes a mono-substituted aluminum dihalide ofthe formula RAlX₂ together with a transition metal andtriphenylphosphine. The catalyst system is similar to that described inU.S. Pat. No. 2,951,066 which uses a mono-substituted aluminum dihalideinstead of alkyl aluminum sesquihalide. The substitution, however, wasnot predictable since it is known that the activity of certain catalystcombinations are highly unpredictable and relatively minor changes incatalyst combinations can lead to liquid polymers rather than solidpolymers.

U.S. Pat. No. 3,284,427 teaches a polymerization of alpha-olefins usinga mixture of aluminum dihalides, transition metals such as titaniumtrichloride and a material from Group VA having the formula R₃ Zrepresented by triphenylphosphine or triphenyl stibine.

British Pat. No. 1,000,348 uses as third component in a Ziegler/Nattasystem an organic compound containing hydrogen and one atom from thegroup consisting of phosphorus, arsenic, and antimony directly bonded toone atom of the group consisting of phosphorus, arsenic, antimony,oxygen, sulfur, nitrogen and halogens. Provided that when the atom fromthe first group is phosphorus, the atom from the second group is notoxygen.

U.S. Pat. No. 3,977,997 provides a process for the manufacture of amodified titanium-containing catalyst for the polymerization ofalpha-olefins of 3-6 carbon atoms. This patent teaches the use of aphosphorus-containing compound and teaches that propylene and butylenecan be polymerized in the presence of a mixture of titanium trichlorideand aluminum trichloride, triphenylphosphine, or tributylphosphine toyield an alpha-olefin polymer.

German Offenlegungsschrift No. 2,441,541 teaches ball milling titaniumtrichloride and a minor amount of aluminum trichloride with phosphineoxide or phosphite or phosphate ester or amide. U.S. Pat. No. 3,092,320teaches the use of a catalyst for the manufacture of polypropylene bypulverizing titanium trichloride in 1/3 mole aluminum trichloride withtributylphosphine in the presence of a finely divided polymer.

However, none of these references, whether taken alone or incombination, teach or suggest a method for obtaining an ultrahighmolecular weight polymer with properties suitable for use as a dragreducing agent. These references are representative but not exhaustiveof the art.

It would therefore be of great benefit to provide a method and acatalyst for an improved polymerization catalyst system for C₂ -C₃₀olefinic hydrocarbons which will provide ultrahigh molecular weight,non-crystalline polymers that are relatively hydrocarbon soluble havinga high polymerization efficiency and suitable for use as a drag reducingagent. While it is recognized ethylene is not per se an alpha-olefin,ethylene will be classified as such for comment throughout thisspecification since ethylene can be present in amounts generally belowabout 10% by weight.

It is therefore an object of the present invention to provide animproved polymerization catalyst for alpha-olefinic hydrocarbons whichwill produce ultrahigh molecular weight, non-crystalline hydrocarbonsoluble polymers by utilizing a catalyst having a high activity orefficiency.

It has now been found in accordance with the instant invention thatultrahigh molecular weight, non-crystalline polymers having goodhydrocarbon solubility can be obtained from a process comprising:

(a) preparing under an inert atmosphere a catalyst comprising:

(1) titanium trichloride of the general formula TiX_(m) wherein m isfrom 2.5 to 4.0;

(2) a cocatalyst such as an organo-aluminum halide of the formulaAlR_(n) X_(3-n) where R is a hydrocarbon radical, X is a halogen and nis 2 or 3 and a

(3) phosphorus compound of the formula PR₁ R₂ R₃ or P(OR₁)(OR₂)(OR₃)where R₁, R₂, and R₃ are, independently, aryl, alkyl, aralkyl, oralkaryl, containing from 1 to 12 carbon atoms and placing the catalystin contact with;

(b) C₂ -C₃₀ α-monoolefinic hydrocarbons under temperature conditionssuitable to form high molecular weight polymers, then

(c) ceasing polymerization at a polymer content level of 20% by weightor less, based on the total reaction mixture.

Reaction conditions of (a) and (b) are generally inert, anhydrous, andtemperatures of from about -25° C. to about 80° C. Pressures can beeither higher or lower than atmospheric, depending on the olefins used.High pressures may be necessary to contain the more volatile ethylene oralpha-olefin compounds. Preferred temperatures are from about 10° C. toabout 30° C.

Thus, according to the instant invention, an aluminum alkyl or aluminumalkyl halide is preferred as a cocatalyst for the titanium trichloride,triphenylphosphine polymerization of an alpha-olefin. The resultingpolymer mixture prepared in accordance with the instant invention can beused as a drag reducing substance or an anti-mist agent. The resultingpolymers produced are of ultrahigh molecular weight, yet are notsuitable to form molded objects, cannot be suitably extruded and cannotsuitably be injected or molded into solid articles.

The instant invention provides for the manufacture of a mixturecontaining an ultrahigh molecular weight non-crystalline polymer in ahydrocarbon solvent. However, the polymer can be manufactured in anolefin with no additional solvent. The entire mixture can then be usedas a drag reducing substance for pumpable liquids or an anti-mist agentfor volatile liquids. Catalyst residues and solvents can be removed fromthe polymer by means of precipitation or washing from the polymer. Thisis well-known in the art. The solid non-crystalline polymer can be addedto pipelines or hydrocarbons. However, for use as a drag reducing agentor anti-mist agent, such steps would not normally be carried out sincethe recovery of raw materials is difficult and additional processingsteps are required with resulting economic loss.

The instant invention provides the most favorable method for preparing adrag reducing polymer or anti-mist agent since the polyolefin isproduced in a hydrocarbon solvent and the entire mixture containingpolyolefin, solvent, and catalyst particles can be used, thus allowinggreat economic efficiency. No separation is required.

Several types of titanium trichloride are available commercially, mostsold by Stauffer Chemical Company. Most are preferred by the reductionof titanium tetrachloride with aluminum. The well-known type 1.1 (or AA)catalyst is titanium trichloride containing approximately 1/3 mole ofaluminum trichloride per mole of titanium chloride. Type 1.13 catalystincludes further additives and produces a higher active catalyst forpropylene polymerization as well as a polymer of higher tacticity.Belgium Patent No. 851,154 teaches a method for preparing a titaniumcatalyst by freshly reducing titanium tetrachloride with aluminum andadding a small amount of monocyclic terpenic ketones or bicyclicterpenic ketones. An inorganic compound can be added to further activatethe catalyst to improve catalyst performance.

When a titanium trichloride catalyst containing monocyclic terpenicketones and bicyclic terpenic ketones was used in place of a catalystnot containing these additives under the same conditions, the rate ofpolymerization increased but the average molecular weight of the productseverely decreased. It is known in the art that low molecular weightalpha-olefin polymers are not effective drag reducing substances whenadded to crude oil being transported in pipelines as taught in U.S. Pat.No. 3,692,676. Drag reduction increases with a polyolefin havingincreased average molecular weight. Alpha-olefinic polymers preparedfrom C₈ to C₁₀ alpha-olefins gave best results. The addition of a smallamount of ultrahigh molecular weight poly(octene-1) to hydrocarbonsbeing pumped showed a drag reduction ranging from 30 to 50%. I havefound that olefinic polymers containing C₂ to C₃₀ α-olefins may produceeffective drag reducers and anti-mist agents.

While α-olefins having from 2 to 30 carbon atoms can be used in thepresent invention, the amount of C₂ to C₇ olefins used must be adjustedto permit dissolution of the non-crystalline polymer in the hydrocarbonsystem in which drag is to be reduced. Normally, 10 weight percent totalof these materials is the maximum useable amount, with lesser amountsnormally used. For each hydrocarbon system, amounts of these lowerolefins are adjusted such that solubility is not adversely affected.

Preferably, the present invention will utilize olefins having from 8 to30 carbon atoms, while olefins of 8 to 12 carbon atoms and mostpreferably 8 to 10 carbon atoms are used. Mixtures of the olefins can beused, too.

The phosphorus containing component of the catalyst mixture is acompound having the general formula PR₁ R₂ R₃ or P(OR₁) (OR₂) (OR₃)wherein each R is independently selected from the group consisting ofaryl, alkyl, aralkyl, cycloalkyl, cycloalkylaryl, or alkaryl containingfrom 1 to 12 carbon atoms. Representative but non-exhaustive examples ofsuch compounds are tri-n-butylphosphine, triethylphosphine,triphenylphosphine, tribenzylphosphine, triethylbutylphosphine,diphenylethylphosphine, tricyclohexylphosphine, dibutylethylphosphine,dioctylphenylphosphine, tributylphosphite, triethylphosphite,triisopropylphosphite, trimethylphosphite, and triphenylphosphite.

The mole ratio of the three components of the catalyst system of theinstant invention will depend upon the specific end result desired.However, generally a ratio of aluminum to phosphorous will range fromabout 0.01 to 0.99, respectively. A mole ratio of Al/phosphorous/Ti of3/0.25-0.50/1.0 is preferred. The catalyst mixture can be simplyprepared by mixing the three components. No extensive milling orcomplicated combination is necessary.

A preferred method for preparing drag reducing substances comprisescontacting α-olefins containing from 2 to 30 carbon atoms with:

(a) titanium trichloride of the general formula TiCl₃.m AlCl₃ wherein mis from 0.00 to 1.00, prepared by a method selected from the groupconsisting of;

(1) reducing titanium tetrachloride with aluminum,

(2) reducing titanium tetrachloride with hydrogen,

(3) reducing titanium tetrachloride with an organometallic compound, or

(4) milling titanium trichloride with AlCl₃ in conjunction with

(b) a cocatalyst such as an organo-aluminum halide of the formulaAlR_(n) X_(3-n) where R is a hydrocarbon radical, X is halogen and n is2 or 3, and a

(c) catalyst modifier of the formula PR₁ R₂ R₃ or P(OR₁) (OR₂) (OR₃)wherein R₁, R₂, and R₃ are, independently aryl, alkyl, aralkyl, oralkaryl containing from 1 to 12 carbon atoms.

The preferred catalyst is crystalline titanium trichloride, prepared byreducing titanium tetrachloride with aluminum of the generalTiCl₃.1/3AlCl₃. This catalyst is sold by the Stauffer Chemical Companyas Type 1.1. Other catalysts can be used, for example, Stauffer's Type1.13 materials. This is also a TiCl₃.1/3AlCl₃ catalyst which has beenactivated chemically and/or physically in its preparation.

The transition metal portion of the catalyst of the instant invention ispreferably comprised of:

(a) a crystalline titanium trichloride prepared by a method selectedfrom the group consisting of

(1) reducing titanium tetrachloride with a metal such as aluminum;

(2) reducing titanium tetrachloride with hydrogen,

(3) reducing titanium tetrachloride with an organometallic compound suchas an aluminum alkyl, or

(4) by milling titanium trichloride with aluminum trichloride togetherwith

(b) 2.5 to 10 weight percent based on the weight of the titaniumtrichloride portion of the catalyst of an effective ketone; and

(c) 0 to 1.0 weight percent based on the total weight of the titaniumtrichloride component of an ionic or polar compound.

Representative but non-exhaustive examples of ionic or polar compoundsare Group IA or IIA metal halides such as sodium bromide, potassiumbromide, sodium chloride, sodium iodide, transition metals, aliphatictriacid salts, alkaline earth metal phosphates and alkyl alkali metalsulfates.

Effective ketones are alkyl ketones having a carbonyl group attacheddirectly to two aliphatic groups, aryl ketones having a carbonyl groupattached directly to two aromatic groups, aralkyl ketones having acarbonyl group attached directly to one aliphatic group and to onearomatic group, cyclic ketones having a carbonyl group attached directlyto a carbocyclic structure. These groups attached directly to thecarbonyl group can have aromatic substituents in the case of alkylgroups, and both aromatic and alkyl substituents in the case of alkylgroups, and both aromatic and alkyl substituents in the case of aryl andcyclic groups.

Representative but non-exhaustive examples of ketones useful in thepractice of the present invention are alkyl ketones such as methyl ethylketone, methyl-n-propyl ketone, benzylacetone, 2-butanone, di-n-hexylketone, 1,1-diphenylacetone, 3-pentanone, 3-methyl-2-butanone,2-heptanone, 3-heptanone, 4-heptanone, 2-hexanone, 3-hexanone,2-nonanone, 5-nonanone, 2-octanone, 4-octanone, 2-pentanone,3-pentanone, phenylacetone; aryl ketones such as benzophenone,2-methylbenzophenone, 4-methylbenzophenone; aralkyl ketones such asacetophenone, 4-acetylbiphenyl, 2-acetylfluorene, 2-acetylphenanthrene,3-acetylphenanthrene, 9-acetylphenanthrene; and carbocyclic ketones suchas bicylo[3.3.1]nonan-9-one, bicylo[3.2.1]octan-2-one, (30 )-camphor,dl-camphor, d-carvone, 1-carvone, cyclobutanone, cyclodecanone,cyclododecanone, 1-decalone, 1-decalone, 2-decalone, 1-indanone,2-indanone, menthone, 1-methyl-2-decalone, norcamphor, (+)-pulegone.Preferred ketones useful in the present invention are saturatedmonocyclic and bicyclic ketones such as camphor, carbomenthone,fenchone, menthone, thujone, verbanone, and verbenone.

The preferred cocatalyst of the instant invention is an alkyl aluminumcompound having the general formula AlR_(n) X_(3-n) where R is ahydrocarbon radical containing 1-20 carbon atoms such as aryl, alkyl,aralkyl, or alkaryl, X is a hydrogen atom and/or halogen atom, and nvaries from 2 to 3. Representative examples of such organoaluminumcompounds which can be used alone or in combination aretrimethylaluminum, triethylaluminum, tri-n-propylaluminum,tri-n-butylaluminum, triisobutylaluminum, tri-n-hexylaluminum,tri(2-methylpentyl)aluminum, tri-n-octylaluminum, diethylaluminumhydride, diisobutylaluminum hydrides, diisopropylaluminum chloride,dimethylaluminum chloride, diethylaluminum chloride, diethylaluminumbromide, diethylaluminum iodide, di-n-propylaluminum chloride,di-n-butylaluminum chloride, diisobutylaluminum chloride, or mixtures ofthese. Mixtures of these organo-aluminum compounds can, of course, beused as the co-catalyst.

The polymerization of the α-olefins can be carried out in a non-solventsystem; that is, the liquid monomers themselves can be utilized as asolvent. However, the polymerization can also be carried out in aninactive hydrocarbon solvent such as branched or straight chainaliphatic compounds. Representative examples of such compounds arepentane, hexane, heptane or octane. Alicyclic hydrocarbon substances canalso be used. Representative examples of such substances are benzene,toluene, and xylene. Analogues of the above hydrocarbons or theirmixtures can be used; for example, LPA solvent (low polynuclear aromaticsolvent, a very high purity aliphatic hydrocarbon having a molecularweight very similar to kerosene and a low aromatic and olefin content,sold by Conoco Inc.).

The catalyst should be handled under an inert atmosphere duringpreparation and polymerization in order to minimize deterioration.Representative examples of suitable inert atmospheres are nitrogen andargon.

A wide range of polymerization conditions can be utilized in the processof the instant invention. Generally the polymerization will be carriedout at pressures from atmospheric to about 1,000 atmospheres, butpressures from 1 to 25 atmospheres are preferred. The polymerizationtemperatures generally will range from about -40° C. to about 100° C.,but preferred temperatures are from about 0° C. to about 50° C.Increasing the temperature will result in an increase in catalytic rate,but will decrease the average molecular weight of the polymer which isnot desired when drag reducing agents are being prepared. Thepolymerization can be carried out either by batch or continuous methods.The polymerization reaction can be conducted either adiabatically orisothermal. The polymerization may be terminated by conventional methodsused for the deactivation of Ziegler-Natta catalysts. For example, thepolymerization can be halted by the addition of a small amount ofalcohol while the polymerization mixture is under an inert atmosphere.

It is essential that the polymerization mixture contains 20 weightpercent or less polymer content based on total reaction mixture. Theresulting drag reducing mixture will then contain less than 20 weightpercent of the ultrahigh molecular weight, non-crystalline hydrocarbonsoluble polyolefin, a hydrocarbon solvent (or unreacted olefins),deactivated catalysts, and a small amount of alcohols (if desired). Theentire mixture can be used as a drag reducing substance. The polymer maybe precipitated by a variety of techniques if desired. These techniquesare well-known to those skilled in this art. In addition, materials canbe added to prevent deterioration of the mixture or corrosion of itsenvironment. For example, materials such as epoxides (propylene oxide)or compounds containing at least one oxirane unit; primary, secondaryand tertiary amines (such as triethylamine, tributylamine,trioctylamine); polyamines; natural amino compounds (such ascoco-propylene diamine) and Group IA and IIA metal hydroxide bases. Inaddition, corrosion inhibitors such as propargyl alcohol or commercialfilm forming materials (such as INHIBITOR 98, trademark of and sold bySherwin-Williams Company) can be used.

It is essential that the polymerization contain 20% by weight or less ofpolymer content based on the total reaction mixture in order to obtain asuitable drag reducing agent. As the polymerization continues to higherlevels, the average molecular weight will rapidly decrease, withincreasing bulk viscosity, making the materials unsuitable for use asdrag reducing agents. It is preferred in the practice of the instantinvention to cease polymerization at polymer content levels ranging fromabout 5 to about 20 weight percent. However, polymer content levels from5 to 15 weight percent are preferred and polymer content levels of from10 to 12% are most preferred, all based on the total reaction mixture.

The invention is more concretely described with reference to theexamples below wherein all parts and percentages are by weight based onthe total reaction mixture, unless otherwise specified. The examples areprovided to illustrate the instant invention and not to limit it.

EXAMPLES 1 THROUGH 6

Polymerizations of octene-1 were conducted at 20°±1° C. bath temperatureusing an olefin charge of 40.0% by weight. Both conventional andphosphine modified systems were compared. The unmodified system wasterminated below 10% by weight and above 30% by weight, while thephosphine modified systems were terminated at levels of about 5, about8, about 15, and about 25% by weight. Drag reduction measurements wereobtained at 10 parts per million and 10 feet per second in a 3/8-inchpipe viscometer.

In carrying out the polymerizations, dried degassed LPA (low polynucleararomatic solvent) was placed into a clean, dry one quart pressurevessel. Diethylaluminum chloride in heptane was added followed by theaddition of the catalyst modifier tri-n-butyl phosphine. Transitionmetal catalyst, titanium trichloride of Stauffer Type 1.1, was thenadded. The mixture was placed into a constant temperature bath andstirred at 290 revolutions per minute for about 30 minutes. A stream ofoctene-1 was added under an inert atmosphere to initiate polymerization.Polymerizations were halted by using isopropanol to deactivate thecatalyst. The ratio of polymerization components was 375/3.0/0.25/1.0(millimoles of octene-1/diethylaluminum chloride/phosphinemodifier/TiCl₃).

The inherent viscosity η_(inh), was determined for each polymer using aCanon-Ubbelohde four bulb shear dilution viscometer (0.1 g polymer/100ml LPA solvent at 25° C.). Inherent viscosities were calculated for eachof the four bulbs. The viscosities were plotted as a function of shearrate. The plot was then used to obtain an inherent viscosity at a shearrate of 300 sec⁻¹.

Drag reduction measurements were made in a 3/8 inch ID pipe viscometerat a flow rate of 10 feet-per-second and diesel oil was the test fluid.In this test, diesel oil was continuously circulated and flowed from a5-gallon storage tank through a Moyno progressive cavity pump into a5-foot test section of 3/8-inch stainless precision tubing and returnedto the 5-gallon tank. The storage tank was temperature controlled by aKryomat constant temperature controller. The temperature of the testsample was maintained at 74° F. and was continuously stirred at lowspeed in the tank.

The pressure drop differences were measured in percent drag reduction ascalculated using the formula: ##EQU1## where ΔP_(base) is the initialbase line pressure of diesel oil without the additive and ΔP_(additive)is the pressure drop with the polymer solution. The results of thesetests are presented in Table 1.

                  TABLE 1                                                         ______________________________________                                        Phosphine Modified Catalyst vs Conventional                                   Ziegler Catalyst                                                                                                   % Drag                                                                        Reduction at 10                                                       Inherent                                                                              ppm polymer                                            Final   Catalytic                                                                            viscosity                                                                             content and                              Ex-  Electron Wt %    Activity                                                                             (dl/gm, 10 fps pumping                           am-  Donor    Poly-   (gm/gm = 300 sec                                                                             velocity                                 ple  Modifier mer     Ti.Hr) sec.sup.-1)                                                                           Initial                                                                             1.0 min.                           ______________________________________                                        1    None     6.75%   222    10.28   44.55 37.88                              2    None     32.77   330    6.65    29.79 23.71                              3    n-Bu.sub.3 P                                                                           4.39    175    11.12   47.77 40.68                              4    n-Bu.sub.3 P                                                                           8.27    248    10.52   45.19 38.93                              5    n-Bu.sub.3 P                                                                           15.34   413    9.37    43.18 37.73                              6    n-Bu.sub.3 P                                                                           25.14   248    9.24    42.11 35.83                              ______________________________________                                    

EXAMPLES 7 THROUGH 16

Dried degassed solvent was placed into a clean and dry 1 quart pressurevessel. Diethylaluminum chloride (DEAC) was added followed bytriphenylphosphine. Titanium catalysts (Stauffer type 1.1 or 1.13) wereadded under an inert atmosphere of dry argon. The type 1.13 catalystcontained camphor, a saturated bicyclic monoterpenic ketone. Theresulting mixture was placed into an agitated water bath and thecatalyst components were allowed to interact for 30 minutes at 290revolutions per minute (rpm). Octene-1 monomer was charged into thereaction vessel. Polymerizations were terminated using 1.7 millilitersisopropyl alcohol to deactivate the catalyst. The polymeric mixture wasstabilized using butyl hydroxytoluene as an antioxidant and propyleneoxide was added to scavenge HCl formed.

For purposes of comparison a catalyst system was prepared underidentical conditions except triphenylphosphine was not used. Comparativedata and results are shown in Table 2. In the table, diethylaluminumchloride is abbreviated DEAC; triphenylphosphine is abbreviated TPP;TiCl₃ (AA) is equaled to TiCl₃.1/3 AlCl₃. The catalyst type refers totitanium trichloride classification of the Stauffer Chemical Company.Catalyst activity is expressed as grams of poly(octene-1) produced pergram of titanium used per hour in LPA as a solvent at 30°±1° C., thepolymerization were initially charged with a 7.5% monomer by weightbased on the total reaction charge, having a catalyst millimole ratio of255/3/1 (octene-1/DEAC/TiCl₃ (AA)) and inh is inherent viscosity in aCanon-Fenske single bulb viscometer (0.1 g polymer/100 ml LPA solvent at25° C.).

In Table 3, LPA was the solvent at a polymerization temperature of25°±1° C. using a 14.8% monomer charge and having a polymerizationcharge ratio of 375/3/1 (millimoles octene-1/DEAC/TiCl₃ obtained fromStauffer Chemical Co.).

                  TABLE 2                                                         ______________________________________                                        EFFECT OF TRIPHENYLPHOSPHINE ON THE                                           ACTIVITY AND INHERENT VISCOSITY FOR THE                                       POLYMERIZATION OF OCTENE-1                                                    Ex-                  mmol  Cata-                                              am-  mmol    mmol    TiCl.sub.3                                                                          lyst  Catalyst                                                                             ηinh dl/g,                        ple  DEAC    TPP     (AA)  Type  Activity                                                                             (single bulb)                         ______________________________________                                        7    2.9     .00     .98   1.1   45.8   6.83                                  8    2.9     .00     .96   1.13  121.0  4.86                                  9    3.0     .36     .99   1.1   65.6   8.05                                  10   3.2     .39     1.1   1.13  138.0  6.92                                  ______________________________________                                    

                                      TABLE 3                                     __________________________________________________________________________    EFFECT OF TRIPHENYLPHOSPHINE                                                  ON THE                                                                        POLYMERIZATION OF OCTENE-1                                                                 mmol                   Reaction                                       mmol                                                                              mmol                                                                              Type 1.13                                                                           Catalyst                                                                           ηinh                                                                             Wt. %                                                                              Time                                      Example                                                                            DEAC                                                                              TPP TiCl.sub.3 (AA)                                                                     Activity                                                                           (single bulb)                                                                        Polymer                                                                            (Hours)                                   __________________________________________________________________________    11   3.4 .00 1.14  167  6.61   8.52 3.02                                      12   3.6 .15 1.20  150  7.64   7.38 2.92                                      13   3.7 .00 1.22  145  6.27   9.55 3.93                                      14   3.5 .17 1.17  134  7.56   8.68 3.82                                      15   3.5 .00 1.16  125  6.16   10.52                                                                              4.98                                      16   3.4 .15 1.12  122  7.54   10.11                                                                              4.95                                      __________________________________________________________________________

A catalyst mixture containing EASC, ethylaluminum sesquichloride, TiCl₃/TPP was investigated for the polymerization of octene-1 in Example 17.The product produced was inferior with respect to drag reducing ability.The catalyst activity was very low and not acceptable for commercialpurposes, although some reaction did occur.

A catalyst mixture consisting of DEAC, TiCl₃ and TPP produced anultrahigh molecular weight product which was acceptable for dragreducing purposes as shown in Example 18. The catalyst system was about25 times more active at the conditions studied than the EASC/TiCl₃ /TPPcatalyst (Example 19).

Level of drag reduction depends on many variables. For example, changesin drag reduction takes place with each change in pipe size, pumpingpressure, type of pumps, temperature, and composition of material (whereeven small variations in hydrocarbon content cause changes).

A polyolefin content greater than about 20 percent by weight is notdesirable because of its high bulk viscosity. At high precent polymercontent the mixture produces low molecular weight polymers. The viscouspolymer mass has poor mass transfer and heat transfer properties, whichfurther lowers the molecular weight of the polymer. Thus the conditionsdescribed are necessary to obtain an ultrahigh molecular weight polymersuitable for drag reduction uses.

The following examples show a comparison of catalyst systems anddemonstrates a catalyst comprising of DEAC/TPP/TiCl₃ produces aneffective drag reducing substance at high rates. The system of theinstant invention outperforms catalyst mixtures consisting of EASC/TiCl₃or EASC/TPP/TiCl₃ or systems such as DEAC/TiCl₃ for the polymerizationof octene-1 to poly(octene-1) in a hydrocarbon solvent of 25°±1° C.Example 17 shows the instant invention while Examples 18, 19 and 20 showthe other systems described. The abbreviations used are identical tothose described for Table 2.

EXAMPLE 17

Distilled, deoxgenated and dry LPA (275 milliliters) was placed into aclean dry 1 quart pressure vessel under dry argon gas. A 10 weightpercent solution of diethylaluminum chloride (2.77 mmols) in heptane wasadded followed by triphenylphosphine (0.23 mmols) and titaniumtrichloride produced by the Stauffer Chemical Company, trademark GradeAA type 1.1, (0.92 mmols TiCl₃ were added under an atmosphere of dryargon with stirring). The resulting mixture was placed in a shaker bathand the catalyst components were allowed to react for 30 minutes at 290rpm at a temperature of 25°±1° C. The monomer, octene-1(38.8 grams) wasintroduced to the reaction vessel to initiate polymerization atatmospheric pressure. Polymerization was continued with stirring for1.37 hours then terminated with isopropyl alcohol (1.7 ml) to deactivatethe catalyst. The polymeric mixture was stabilized using butylatedhydroxy toluene as an antioxidant (1.7 ml) and propylene oxide was addedto scavenge any hydrochloride present. At the termination of thepolymerization, 77.38 grams of the mixture was poured into 400 ml ofisopropanol with sufficient mixing to precipitate a viscous material.The substance was washed with 400 ml of isopropanol, filtered and washedwith 400 ml of methanol to remove catalyst residue. The poly(octene-1)was collected by filtration and dried in a vacuum oven. The inherentviscosity of the polymer was determined to by 9.38 dl/gm in a singlebulb Canon-Fenske viscometer in the usual manner.

EXAMPLE 18

A comparative example was carried out using diethylaluminum chloride andTiCl₃ (type 1.1) in the absence of triphenylphosphine as a catalystmodifier. The polymerization method used in Example 17 was followed forthis polymerization of octene-1. The inherent viscosity of the polymerobtained was 7.90 dl/gm. The comparison clearly demonstrates that theaddition of a phosphine compound to the DEAC/TiCl₃ catalyst systemenhances average molecular weight of the polymer as measured by inherentviscosity. It is also demonstrated that the addition of the modifierincreased the activity of the catalyst as determined by grams ofpoly(octene-1) produced per gram of titanium used per hour in LPA as thesolvent at 25°±1° C. using a 14.8 weight percent monomer charge.

EXAMPLE 19

A comparative example is carried out using a catalyst system employingethylaluminum sesquichloride (EASC), triphenylphosphine, titaniumtrichloride for the polymerization of octene-1. The polymerizationmethod was identical to Example 17 except that EASC was used as aco-catalyst. The inherent viscosity of the poly(octene-1) produced was3.77 dl/gm. The catalyst activity was 7.53 grams of polymer per gram oftitanium per hour. The polymer obtained was unacceptable as a dragreducing substance. In addition, the catalyst activity was low and notacceptable for most commercial applications.

EXAMPLE 20

A third comparative example was carried out using a 2-component catalystsystem comprising ethylaluminum sesquichloride and titanium trichloridefor the polymerization of octene-1 at 25°±1° C. Triphenylphosphine wasnot added to the catalyst mixture. In other respects the polymerizationwas carried out identically to that described in Example 17. Theinherent viscosity of the poly(octene-1) produced was 4.3 dl/gm and thecatalyst had an activity of 8.75 grams of polymer per gram of titaniumper hour.

All pertinent results and comparative data for examples 17 through 20are shown in tabular form in Table 4.

                                      TABLE 4                                     __________________________________________________________________________    EFFECT OF VARIOUS CATALYSTS ON THE ACTIVITY AND INHERENT                      VISCOSITY FOR THE POLYMERIZATION OF OCTENE-1                                                                    ηinh                                                            Catalyst                                                                           Wt. %                                                                              (dl/gm,                                     Example                                                                            Catalyst Ratio                                                                             Mole Ratio                                                                          Activity                                                                           Polymer                                                                            single bulb)                                __________________________________________________________________________    17   DEAC--TPP--TiCl.sub.3 (1.1)                                                                3:0.25:1                                                                            181  4.18 9.38                                        18   DEAC--TiCl.sub.3 (1.1)                                                                     3:1   142  5.22 7.90                                        19   EASC--TPP--TiCl.sub.3 (1.1)                                                                3:0.25:1                                                                            7.53 2.37 3.77                                        20   EASC--TiCl.sub.3 (1.1)                                                                     3:1   8.75 2.85 4.30                                        __________________________________________________________________________

Examples 21 and 22 were carried out to determine relative crystallinityof the solid-drag reducing component.

Samples of poly(octene-1) using a tri-n-butyl phosphine modified systemwere compared with samples of a poly(octene-1) using a conventionalcatalyst system. After obtaining polymers, two samples were placed onindented glass slides, pressed flat with a microscope slide and heldflat in a vise for 72 hours. The flattened samples were scanned with CuKαradiation and the diffraction patterns recorded. Both samples yield acharacteristic non-crystalline diffraction pattern similar to thoseobtained from liquids, and is described in "X-Ray Diffraction Patternsof Polymers" by J. W. Turley, Dow Chemical Company, Midland, Mich.,1964. The pattern showed two broad maxima at approximately 14 and 4.6angstroms which indicated that the certain spacings within the polymersoccur with a particular high frequency.

EXAMPLE 21

Dried, degassed low polynuclear aromatic (LPA) solvent was placed into aclean dry 1 quart pressure vessel. Diethylaluminum chloride was addedfollowed by the addition of titanium trichloride catalyst obtained fromStauffer Chemical Company (Type 1.1, TiCl₃.1/3AlCl₃). The materials wereadded under inert atmosphere of dry argon. The resulting mixture wasplaced into an agitated water bath and the catalyst components wereallowed to interact for 30 minutes while stirring at 290 rpm. Thepolymerization was initiated by the addition of octene-1 (obtained fromEthyl Corporation). The polymerization was terminated 40 minutes laterby the addition of 1.7 ml of isopropyl alcohol with mixing in order todeactivate the catalyst. The polymer mixture was stabilized usingbutylated hydroxy toluene (BHT) as an antioxidant. The polymerizationwas initially charged with 40% weight octene-1 and LPA as apolymerization diluent. The starting temperature was 20°±1° C. The ratioof polymerization compounds was 357/3/1 (millimoles ofoctene-1/diethylaluminum chloride/TiCl₃.AA).

In determining weight of polymer produced, 46 grams of deactivatedpolymer mixture was placed into a 400 ml of isopropanol with sufficientmixing to precipitate a viscous material containing poly(octene-1). Thesubstance was washed with an additional 400 ml of isopropanol filteredand washed with 400 ml of methanol to remove catalyst residues.Poly(octene-1) was collected by vacuum filtration and dried in a vacuumoven overnight to obtain a control polymer.

Example 22 shows the polymerization method of the instant invention.

EXAMPLE 22

Dried, degassed LPA as a solvent (78 ml) was placed in a clean dry 1quart pressure vessel. Diethylaluminum chloride (3.15 millimoles) wasadded followed by the addition of tri-n-butyl phosphine (0.26millimoles). A titanium trichloride catalyst (1.05 millimoles) was addedhaving the formula TiCl₃.1/3AlCl₃ (type 1.1 from Stauffer ChemicalCompany).

Polymerization materials were combined under an inert atmosphere of dryargon. The resulting mixture was placed into a shaker bath and agitatedat 290 revolutions per minute at 20°±1° C. for 30 minutes.

Polymerization was initiated using 62.4 ml of octene-1 from EthylCorporation. The olefin was dried with molecular sieves and degassedwith argon. Initially the polymerization contained about 40% monomer byweight.

The polymerization reaction was terminated 33 minutes later by adding1.7 ml of isopropyl alcohol to deactivate the catalyst. The polymer wasstabilized using butylated hydroxy toluene as an antioxidant.

In determining the weight percent of polymer produced, 42 grams of thedeactivated mixture was placed into 400 ml of isopropanol withsufficient mixing to precipitate a viscous material containingpoly(octene-1). The material was washed with an additional 400 ml ofisopropanol filtered and washed with 400 ml of methanol to removecatalyst residues. The poly(octene-1) was collected by vacuum filtrationand dried in a vacuum oven overnight to obtain a polymer from thephosphine modified catalyst system. The polymerization produced 4.39%polymer by weight with an inherent viscosity of 11.12 deciliters pergram at a shear rate of 300 sec⁻¹ (0.1 grams of polymer/100 ml of LPA at25° C.) in a four-bulb Canon-Ubbelohde viscometer.

Thus, according to the instant invention, a catalyst comprising atitanium halide and an organoaluminum halide with a phosphine compoundis shown to produce polymer mixtures useful as drag reducing substancesor antimist agents under the specific conditions outlined in thisapplication. The resulting polymers are non-crystalline and of ultrahighmolecular weight, but are not suitable to form molded objects. Theproducts of the instant invention cannot be easily extruded to form pipeor tubing having rigid properties and cannot be easily injection molded.The use of a ketone in conjunction with a phosphorus-modifiedTiCl₃.mAlCl₃ polymerization catalyst provides an improved reaction,wherein catalyst activity is greatly enhanced while maintaining productpolymer inherent viscosity; in contrast to high activity, low inherentviscosity found when using ketones only, and low activity, high inherentviscosity found when using phosphorus compounds only.

While certain embodiments and details have been shown for the purpose ofillustrating this invention, it will be apparent to those skilled inthis art that various changes and modifications may be made hereinwithout departing from the spirit or scope of the invention.

I claim:
 1. A method for the production of ultrahigh molecular weightnon-crystalline hydrocarbon soluble polymers comprising:(a) preparingunder an inert atmosphere a catalyst comprising(1) titanium trichloride,(2) a co-catalyst of the formula AlR_(n) X_(3-n) where R is ahydrocarbon radical containing from 1 to 20 carbon atoms, X is hydrogenor halogen, and n is 2 or 3, and a phosphorus compound of the formulaPR₁ R₂ R₃, wherein R₁, R₂, and R₃ are, independently, aryl, alkyl,aralkyl, or alkaryl, each containing from 1 to 12 carbon atoms andplacing the catalyst in contact with (b) C₂ to C₃₀ monoolefinichydrocarbons, said contacting occurring at temperatures of from about-10° C. to about 40° C. to polymerize said olefins, then (c) ceasingpolymerization at a polymer content level of 20% by weight or less basedon the total reaction mixture.
 2. A method as described in claim 1wherein the catalyst comprises a crystalline titanium trichlorideprepared by a method selected from the group consisting of reducingtitanium tetrachloride with(1) aluminum, or (2) hydrogen, or (3)organo-aluminum compound, and (4) milling titanium trichloride withaluminum chloride.
 3. A method as described in claim 1 wherein thecatalyst comprises:(a) crystalline titanium trichloride prepared by amethod selected from the group consisting of(1) reducing titaniumtetrachloride with aluminum, (2) reducing titanium tetrachloride withhydrogen, (3) reducing titanium tetrachloride with an organo metalliccompound and (4) milling titanium trichloride with aluminum trichloride(b) 2.5 to 10 weight percent based on the weight of the titaniumtrichloride component of a ketone and, (c) 0-1.0 weight percent basedupon the total weight of the titanium trichloride component of an ionicor polar compound selected from the group consisting of Group IA or IIAmetal halides.
 4. A method as described in claim 2 wherein the catalysthas the general formula TiCl₃.mAlcl₃ wherein m is from 0.00 to 1.0.
 5. Amethod as described in claim 2 wherein polymerization is ceased at apolymer content level of about 10-12% by weight, based on the totalreaction mixture.
 6. A method as described in claim 2 wherein theorgano-aluminum compound is selected from the group consisting oftrimethylaluminum, triethylaluminum, tri-n-propylaluminum,tri-n-butylaluminum, triisobutylaluminum, tri-n-hexylaluminum,tri(2-methyl pentyl) aluminum, tri-n-octylaluminum, diethylaluminumhydride, diisobutylaluminum hydrides, dimethylaluminum chloride,diethylaluminum chloride, diethylaluminum bromide, diethylaluminumiodide, di-n-propylaluminum chloride, di-n-butylaluminum chloride,diisobutylaluminum chloride, and mixtures of these.
 7. A method asdescribed in claim 4 wherein the mole ratio of aluminum to phosphoruscompound is from about 0.01 to 0.99.
 8. A method as described in claim 7wherein the ratio of aluminum to titanium compound is from 0.1 to 500.9. A method as described in claim 5 wherein the mole ratio of thephosphine component to the cocatalyst is from about 0.01 to about 1,respectively.
 10. A method as described in claim 6 wherein thepolymerization is carried out in an inactive hydrocarbon solvent.
 11. Amethod as described in claim 7 wherein the solvent is selected from thegroup consisting of pentane, hexane, heptane, octane, benzene, toluene,xylene, and mixtures of these.
 12. A method as described in claim 8wherein the polymerization is carried out under an inert atmosphere. 13.A method as described in claim 12 wherein the inert atmosphere isselected from the group consisting of nitrogen, xenon, and argon.
 14. Amethod as described in claim 3 wherein the ketone is selected from thegroup consisting of camphor, carbomenthone, fenchone, menthone, thujone,verbanone, or verbenone.